diff --git a/python/lsst/ci/middleware/mock_dataset_maker.py b/python/lsst/ci/middleware/mock_dataset_maker.py
index 2609f62..2b5eeba 100644
--- a/python/lsst/ci/middleware/mock_dataset_maker.py
+++ b/python/lsst/ci/middleware/mock_dataset_maker.py
@@ -125,9 +125,9 @@ def make_datasets(self, dataset_type: DatasetType, run: str = MISC_INPUT_RUN) ->
             return
         if not self.butler.registry.registerDatasetType(dataset_type):
             return
-        if (data_ids := self.cached_data_ids.get(dataset_type.dimensions.as_group())) is None:
+        if (data_ids := self.cached_data_ids.get(dataset_type.dimensions)) is None:
             remaining_skypix_dimensions, dimensions = self._split_dimensions(
-                dataset_type.dimensions.as_group()
+                dataset_type.dimensions
             )
             data_ids = self._get_bounded_data_ids(dimensions)
             while remaining_skypix_dimensions: